Synthesis and characterization of 4-cyanobiphenyl-4?-yloxy-functionalized poly(7-oxanorbornene-5,6-exo-dicarboximide)s via ring opening metathesis polymerization (ROMP)

Abstract

N‐[n‐(4‐cyanobiphenyl‐4′‐yloxy)alkyl]‐7‐oxanorbornene‐5,6‐exo‐dicarboximide (CBON2–CBON8) with increasing number of methylene groups in the alkyl part (n = 2–8) were synthesized by Mitsunobu condensation between the appropriate alcohols (CBA2–CBA8) and 7‐oxanorbornene‐5,6‐exo‐dicarboximide (ON). The conditions for the ring opening metathesis polymerization of CBONn giving acceptable molecular weights and molecular distributions were established. Characterization of the resulting polymers (P2–P8) by 1H‐ and 13C‐NMR has shown a high trans content. Differential scanning calorimetry and optical microscopy analysis have shown that the alcohols CBAn are thermotropic with some variations between the first and second heating‐cooling cycles, the monomers CBONn melt with no evidence of any mesomorphic state, the polymers Pn show only the glass transition, and the glass transition temperature (Tg) decreases with increases in the spacer length. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 2807–2821, 1998

Liquid Crystalline Polymers by Metathesis Polymerization

“…Polymerization was carried out with Schrock type initiator 4. The dicarboximide linkage probably hindered the formation of LC phases; even the introduction of relatively long spacers between the polymer backbone and the mesogen did not lead to liquid crystalline monomers or polymers [41].…”

“…Figure 8 shows some examples of backbone structures bearing the cyanobiphenyl-moiety that have been reported in literature. The above-mentioned ROMP-derived polymers poly-(II-n) [39], poly-(IV-n) [42,47], poly-(VI-n) [41], and poly-(VII-n) [53] will be compared with each other and with acrylate-based [56][57][58][59], siloxanebased [60] and vinylcyclopropane-based systems [61]. The detected mesophases and their transition temperatures are summarized in Table 6.…”

High temperature polymer dielectrics from the ring opening metathesis polymerization (ROMP)

“…The 7-oxanorbornene monomers can be easily synthesized and modified in order to add diverse chemical functionality. [4][5][6] 7-oxanorbornenes can be polymerized using ring opening metathesis polymerization (ROMP), a living polymerization that allows very good control over the final polymer molecular weights.…”

Ring-opening metathesis polymerization of 2-(S)-(-)-endo-D-pantolacton-O-yl norbornene-2-carboxylate using a classical ROMP catalyst. Synthesis and characterization of optically active poly(norbornene-2-carboxylic acid)

“…The targeting of polymer stereoregularity implies isomeric purity of the monomers joined to specificities in the ring-opening reaction. Because of structure and isomeric purity of monomers, improvements in stereoregularity were obtained polymerizing 2,3-disubstituted norbornadiene 5,[8][9][10] , enantiomerically pure 5,6-disubstituted norbornene 5,9,11) , purely exo-5,6-disubstituted-7-oxanorbornene 12) and monosubstituted norbornene 13) . In the ring-opening reaction, stereospecificities and enantiospecificities which make possible improvements in cis or trans and in cis-racemo or trans-meso diads regulariFull Paper: ROMP of the optical pure monomer of the title compound (1) was performed successfully using the classical WCl 6 /SnMe 4 catalyst.…”